TY - JOUR AU - Popp,David TI - International Innovation and Diffusion of Air Pollution Control Technologies: The Effects of NOX and SO2 Regulation in the US, Japan, and Germany JF - National Bureau of Economic Research Working Paper Series VL - No. 10643 PY - 2004 Y2 - July 2004 UR - http://www.nber.org/papers/w10643 L1 - http://www.nber.org/papers/w10643.pdf N1 - Author contact info: David Popp Department of Public Administration and International Affairs Syracuse University The Maxwell School 426 Eggers Hall Syracuse, NY 13244-1020 Tel: 315/443-2482 Fax: 315/443-1081 E-Mail: dcpopp@maxwell.syr.edu AB - Using patent data from the United States, Japan, and Germany, this paper examines both the innovation and diffusion of air pollution control equipment. Whereas the United States was an early adopter of stringent sulfur dioxide (SO2) standards, both Japan and Germany introduced stringent nitrogen dioxide (NOX) standards much earlier than the US. Nonetheless, in both cases, tightened standards in the U.S. led to more domestic patenting, but not more foreign patenting. Overall, the data suggest that inventors respond to environmental regulatory pressure in their own country, but not to foreign environmental regulations. Moreover, any technology transfer that occurs appears to be indirect. Domestic innovation occurs even for technologies that have already experienced significant innovative activity abroad. Moreover, utilities in countries that adopt regulations later nonetheless purchase pollution abatement equipment from domestic firms. However, patent citation data from the U.S. show that earlier foreign patents are an important building block for NOX pollution control innovations in the U.S., suggesting that American inventors build on technological advances made in countries that adopted stringent regulation earlier. ER -